[NTG-context] Metapost graphic in setupbackground

Hi all, I make my first steps with Metapost. I would like to set the background of all pages to a Metapost graphic. But only the first page has the defined background. I also tried with \startuseMPgraphic with no success --- mwe --- \startreusableMPgraphic{kreis} draw fullcircle scaled 70mm withcolor red withpen pencircle scaled 6mm; \stopreusableMPgraphic \definelayer[kreisbackground][width=70mm,height=70mm] \setlayer[kreisbackground] [x=-3mm,y=-3mm] {\reuseMPgraphic{kreis}} \setupbackgrounds[paper][background=kreisbackground, state=start] \starttext \input lorem \page \input lorem \stoptext TIA juh